From 6a8b58a3ce6dc162cae4b74ca8f39392672e6cba Mon Sep 17 00:00:00 2001
From: panpingsheng <panpingsheng@hygon.cn>
Date: Sat, 12 Jun 2021 15:15:29 +0800
Subject: [PATCH] target/i386: get/set/migrate GHCB state

GHCB state is necessary to CSV2 guest when migrating to target.

Add GHCB related definition, it also adds corresponding part
to kvm_get/put, and vmstate.

Signed-off-by: hanliyang <hanliyang@hygon.cn>
---
 linux-headers/linux/kvm.h  |  2 ++
 target/i386/cpu.h          |  5 +++++
 target/i386/kvm/kvm.c      | 11 +++++++++++
 target/i386/kvm/sev-stub.c |  2 ++
 target/i386/machine.c      | 24 ++++++++++++++++++++++++
 target/i386/sev.c          | 10 ++++++++++
 target/i386/sev.h          |  2 ++
 7 files changed, 56 insertions(+)

diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
index e9cd0ebaf1..e796105b76 100644
--- a/linux-headers/linux/kvm.h
+++ b/linux-headers/linux/kvm.h
@@ -1203,6 +1203,8 @@ struct kvm_ppc_resize_hpt {
 
 #define KVM_CAP_ARM_TMM 300
 
+#define KVM_CAP_SEV_ES_GHCB 500
+
 #define KVM_CAP_ARM_VIRT_MSI_BYPASS 799
 
 #define KVM_EXIT_HYPERCALL_VALID_MASK (1 << KVM_HC_MAP_GPA_RANGE)
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 6993552cd9..a9a646bba2 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -520,6 +520,8 @@ typedef enum X86Seg {
 
 #define MSR_VM_HSAVE_PA                 0xc0010117
 
+#define MSR_AMD64_SEV_ES_GHCB           0xc0010130
+
 #define MSR_IA32_XFD                    0x000001c4
 #define MSR_IA32_XFD_ERR                0x000001c5
 
@@ -1885,6 +1887,9 @@ typedef struct CPUArchState {
 
     /* Number of dies within this CPU package. */
     unsigned nr_dies;
+
+    /* GHCB guest physical address info */
+    uint64_t ghcb_gpa;
 } CPUX86State;
 
 struct kvm_msrs;
diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index 5730d0e0c0..9e65242739 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -3625,6 +3625,10 @@ static int kvm_put_msrs(X86CPU *cpu, int level)
         }
     }
 
+    if (sev_kvm_has_msr_ghcb) {
+        kvm_msr_entry_add(cpu, MSR_AMD64_SEV_ES_GHCB, env->ghcb_gpa);
+    }
+
     return kvm_buf_set_msrs(cpu);
 }
 
@@ -3999,6 +4003,10 @@ static int kvm_get_msrs(X86CPU *cpu)
         }
     }
 
+    if (sev_kvm_has_msr_ghcb) {
+        kvm_msr_entry_add(cpu, MSR_AMD64_SEV_ES_GHCB, 0);
+    }
+
     ret = kvm_vcpu_ioctl(CPU(cpu), KVM_GET_MSRS, cpu->kvm_msr_buf);
     if (ret < 0) {
         return ret;
@@ -4319,6 +4327,9 @@ static int kvm_get_msrs(X86CPU *cpu)
         case MSR_ARCH_LBR_INFO_0 ... MSR_ARCH_LBR_INFO_0 + 31:
             env->lbr_records[index - MSR_ARCH_LBR_INFO_0].info = msrs[i].data;
             break;
+        case MSR_AMD64_SEV_ES_GHCB:
+            env->ghcb_gpa = msrs[i].data;
+            break;
         }
     }
 
diff --git a/target/i386/kvm/sev-stub.c b/target/i386/kvm/sev-stub.c
index 99899688e4..a0aac1117f 100644
--- a/target/i386/kvm/sev-stub.c
+++ b/target/i386/kvm/sev-stub.c
@@ -14,6 +14,8 @@
 #include "qemu/osdep.h"
 #include "sev.h"
 
+bool sev_kvm_has_msr_ghcb;
+
 int sev_kvm_init(ConfidentialGuestSupport *cgs, Error **errp)
 {
     /* If we get here, cgs must be some non-SEV thing */
diff --git a/target/i386/machine.c b/target/i386/machine.c
index a1041ef828..9a1cb8f3b8 100644
--- a/target/i386/machine.c
+++ b/target/i386/machine.c
@@ -1605,6 +1605,27 @@ static const VMStateDescription vmstate_triple_fault = {
     }
 };
 
+#if defined(CONFIG_KVM) && defined(TARGET_X86_64)
+static bool msr_ghcb_gpa_needed(void *opaque)
+{
+    X86CPU *cpu = opaque;
+    CPUX86State *env = &cpu->env;
+
+    return env->ghcb_gpa != 0;
+}
+
+static const VMStateDescription vmstate_msr_ghcb_gpa = {
+    .name = "cpu/svm_msr_ghcb_gpa",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .needed = msr_ghcb_gpa_needed,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT64(env.ghcb_gpa, X86CPU),
+        VMSTATE_END_OF_LIST()
+    }
+};
+#endif
+
 const VMStateDescription vmstate_x86_cpu = {
     .name = "cpu",
     .version_id = 12,
@@ -1751,6 +1772,9 @@ const VMStateDescription vmstate_x86_cpu = {
 #endif
         &vmstate_arch_lbr,
         &vmstate_triple_fault,
+#if defined(CONFIG_KVM) && defined(TARGET_X86_64)
+        &vmstate_msr_ghcb_gpa,
+#endif
         NULL
     }
 };
diff --git a/target/i386/sev.c b/target/i386/sev.c
index 6ba71c91d7..7744378112 100644
--- a/target/i386/sev.c
+++ b/target/i386/sev.c
@@ -152,6 +152,8 @@ QEMU_BUILD_BUG_ON(sizeof(PaddedSevHashTable) % 16 != 0);
 static SevGuestState *sev_guest;
 static Error *sev_mig_blocker;
 
+bool sev_kvm_has_msr_ghcb;
+
 static const char *const sev_fw_errlist[] = {
     [SEV_RET_SUCCESS]                = "",
     [SEV_RET_INVALID_PLATFORM_STATE] = "Platform state is invalid",
@@ -1198,6 +1200,14 @@ int sev_kvm_init(ConfidentialGuestSupport *cgs, Error **errp)
     cgs_class->memory_encryption_ops = &sev_memory_encryption_ops;
     QTAILQ_INIT(&sev->shared_regions_list);
 
+    /* Determine whether support MSR_AMD64_SEV_ES_GHCB */
+    if (sev_es_enabled()) {
+        sev_kvm_has_msr_ghcb =
+                kvm_vm_check_extension(kvm_state, KVM_CAP_SEV_ES_GHCB);
+    } else {
+        sev_kvm_has_msr_ghcb = false;
+    }
+
     cgs->ready = true;
 
     return 0;
diff --git a/target/i386/sev.h b/target/i386/sev.h
index 209c92fd6f..0bfe3879ef 100644
--- a/target/i386/sev.h
+++ b/target/i386/sev.h
@@ -78,4 +78,6 @@ void sev_del_migrate_blocker(void);
 
 int sev_kvm_init(ConfidentialGuestSupport *cgs, Error **errp);
 
+extern bool sev_kvm_has_msr_ghcb;
+
 #endif
-- 
2.41.0.windows.1